A. Field of the Invention
The present invention relates to a method and device for routing and completing telephone calls. More particularly, the present invention relates to treating a telephone call at a Services Node prior to completing the call to the appropriate telephone number.
B. Description of the Related Art
A Personal Access Service ("PAS") allows a telephone subscriber to be reached at different locations by dialing a single telephone number that accesses the PAS system. PAS directs the telephone call to the appropriate telephone number where the called subscriber is likely to be reached according to a programmed criterion. For example, telephone calls to people who work in their business office during the morning but work from home during the afternoon can be routed to their office telephone during the morning hours and to their home telephone during the afternoon and evening hours.
U.S. Pat. No. 5,592,541 to Fleischer et al. describes the forwarding of incoming telephone calls defined by a routing list including alternate telephone numbers to which calls originally placed to the subscriber's number may be routed in an attempt to reach the subscriber. The routing list may forward all incoming calls to other telephone numbers or may forward only calls from selected groups of one or more telephone numbers. Incoming calls may be forwarded according to the time of the day, day of the week, a percentage allocation, a specific date or the originating location of the call.
U.S. Pat. No. 5,556,235 to Hetz describes an Integrated Services Control Point ("ISCP") of an Advanced Intelligent Network ("AIN") which routes telephone calls based on an internal criteria. The call routing criteria are maintained in a database and may be based on the time of the day or the telephone number was dialed.
Typically, PAS uses a computer system to store routing profiles specifying where telephone calls to PAS subscribers should be directed. Callers trying to reach PAS subscribers dial the PAS access telephone number associated with the subscriber they wish to reach. PAS determines the subscriber that the caller is trying to reach and where the call should be routed from the subscriber's routing profile. PAS then sends the call to the appropriate telephone number.
One problem with this PAS arrangement is the subscriber must maintain and callers must dial a separate telephone number to access the PAS system. The PAS access telephone number is a different telephone number than the subscribers' home or office telephone numbers where they are normally reached. Simply forwarding an existing telephone number, such as a subscriber's existing home or business telephone number, to PAS does not work. Callers attempting to reach subscribers at their existing home or office telephone numbers will be forwarded to the PAS system. However, when PAS determines that the call should be routed back to the subscribers' home or office, the telephone number is still set to forward the call to PAS. To address this problem, the office telephone number could be forwarded to PAS, but then a second line would have to be added to receive the telephone call from PAS. Thus, telephone subscribers must still maintain a separate telephone number to allow the callers trying to reach them to access the PAS system.